Human Colorectal Cancer Cells Induce T-Cell Death Through Release of Proapoptotic Microvesicles: Role in Immune Escape

Department of Experimental Medicine, Sapienza University of Rome, Roma, Latium, Italy
Gastroenterology (Impact Factor: 16.72). 07/2005; 128(7):1796-804. DOI: 10.1053/j.gastro.2005.03.045
Source: PubMed


Normal and neoplastic cells release microvesicles, whose effects on the immune system still need to be elucidated. Because human colorectal cancer cells are hypothesized to escape immune recognition by expressing proapoptotic molecules, we investigated whether microvesicles bearing Fas ligand and tumor necrosis factor-related apoptosis-inducing ligand and inducing apoptosis of activated T cells are secreted by colorectal cancer cells both in vitro and in affected patients.
Fas ligand and tumor necrosis factor-related apoptosis-inducing ligand expression were analyzed in colorectal cancer cells and purified microvesicles by flow cytometry, Western blotting, and immunoelectron microscopy. Microvesicle tumor origin was assessed through simultaneous detection of lysosomal (CD63) and adenocarcinoma (carcinoembryonic antigen) markers. Proapoptotic activity of microvesicles was evaluated by annexin V/propidium iodide staining and caspase activation in T cells, including CD8+ T lymphocytes from colorectal cancer patients.
Colorectal cancer cells showed a granular pattern of tumor necrosis factor-related apoptosis-inducing ligand and Fas ligand expression, suggesting a secretory behavior. These proapoptotic molecules were detected on isolated microvesicles, together with class I HLA, CD63, and carcinoembryonic antigen. Microvesicles induced Fas ligand-mediated and tumor necrosis factor-related apoptosis-inducing ligand-mediated apoptosis of activated CD8+ T cells generated from colorectal cancer patients. Microvesicles with comparable phenotypes and functions were found in plasma from patients with advanced disease, whereas vesicular structures expressing Fas ligand and tumor necrosis factor-related apoptosis-inducing ligand were also detected in colorectal cancer specimens.
These data show that colorectal cancer induces T-cell apoptosis through the release of Fas ligand-bearing and tumor necrosis factor-related apoptosis-inducing ligand-bearing microvesicles both in vitro and in vivo. This mechanism of immune escape has potential implications as a prognostic factor and could be targeted for the development of new antitumor therapies in colorectal cancer patients.

Download full-text


Available from: Marisa Colone
  • Source
    • "Tumor derived exosomes have been shown to transport apoptosis inhibitory proteins, such as survivin, which is induced under stress conditions, in order to promote survival[66].Yang et al. (2013) andFranzen et al. (2014)have also shown that bladder cancer cell derived exosomes inhibit tumor cell apoptosis through inhibition of the Akt and ERK pathways[67,68]. furthermore, others have reported that cancer cell derived exosomes can create an immunosuppressive microenvironment via induction of T-cell apoptosis and this was imparted via induction of adenosine[20,69]as well as FAS-FASL ligation[70,71]. In agreement with what has been reported, our results indicate that PCa derived exosomes inhibit apoptosis in both cancer and benign prostate cell lines, and potentially promote tumorigenesis. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Prostate cancer (PCa) is the leading type of cancer diagnosed in men. Studies on tumour-related extracellular vesicles (EVs) suggest that exosomes play a significant role in paracrine signaling pathways thus potentially influencing cancer progression via different mechanisms.During last decade numerous studies have revealed the role of EVs in the progression of various pathological conditions including cancer. We have previously described the role of exosomes as potential biomarkers for PCa. Differences in proteomic, lipidomic, and cholesterol content of exosomes derived from PCa cell lines versus benign prostate cell lines confirmed that exosomes are good candidates for future biomarker studies. Our extensive proteomic analysis completed alongside with the evidence of exosome uptake into a local tumour microenvironment have encouraged us to further examine the role of these vesicles in distinct mechanisms involved in the progression of PCa and castration resistant PCa.In this study, we hypothesize that exosomes play a pivotal role in cell-cell communication in the local tumour microenvironment, conferring activation of numerous survival mechanisms during PCa progression and development of therapeutic resistance. Our in vitro results demonstrate that PCa derived exosomes significantly reduce apoptosis in LNCaP and RWPE-1 cells increase cancer cell proliferation and induce cell migration. Consistently with our in vitro findings, we have demonstrated that exosomes increase tumor volume and PSA level in vivo when xenograft bearing mice were administered intravenously with DU145 exosomes.This research suggests that exosomes derived from PCa cells, regardless of the androgen receptor phenotype, attribute positively the of mechanisms that contribute to PCa progression.
    Full-text · Article · Jan 2016 · Oncotarget
  • Source
    • "We can also detect cell-specific composition and abundance of proteins such as Survivin in exosomes that may be useful to reveal different cellular behaviors. Exosomes from various cancer cells express Fas ligand which induces T-cell apoptosis and abolishes the function of adaptive immune cells (Andreola et al., 2002; Huber et al., 2005). Alternatively, platelet-derived exosomes were shown to transfer integrins to breast and lung cancer cells (Janowska-Wieczorek et al., 2005). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The tumor microenvironment plays an integral part in the biology of cancer, participating in tumor initiation, progression, and response to therapy. Factors released by tumor cells themselves contribute in creating an environment mostly favorable but sometimes detrimental to the tumor. Survivin, one of the key members of the inhibitor of apoptosis (IAP) family of proteins, has been shown in the cytoplasm, mitochondria, nucleus, and most recently in the extracellular space, transported via small membrane bound vesicles called exosomes. Exosomes are secreted from hematopoietic, non-hematopoietic, tumor, and non-tumor cells, shuttling essential molecules such as proteins, RNAs, and microRNAs, all believed to be important for cell-cell and cell-extracellular communication. In this review, we discuss exosomal Survivin and its role in modifying the tumor microenvironment.
    Full-text · Article · Jun 2015 · Histology and histopathology
    • "When encountering Fas-positive (CD95) lymphocytes, these EV induce apoptotic death [24] . This was also confirmed as a phenomenon in colorectal cancer [25] and as a property of vesicles isolated from the sera of ovarian cancer patients [26] . In nasopharyngeal carcinoma, a tumour related to Epstein Barr virus (EBV) infection, circulating EV exhibit high levels of Galectin-9, which mediates interactions with CD4 + helper T cells through the Tim-3 receptor. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The tumour microenvironment is a highly complex and dynamic tissue. It comprises not only neoplastic cells, but also other resident cells within the milieu such as stroma and vascular cells in addition to a variable cellular infiltrate from the periphery. A host of soluble factors such as growth factors, chemokines, eicosanoids soluble metabolites and extracellular matrix components have been extensively documented as factors which modulate this environment. However, in recent years there has also been growing interests in the potential roles of extracellular vesicles (EV) in many of the processes governing the nature of cancerous tissue. In this brief review, we have assembled evidence describing several distinct functions for extracellular vesicles in modulating the microenvironment with examples that include immune evasion, angiogenesis and stromal activation. Whilst there remains a great deal to be learnt about the interplay between vesicles and the cancerous environment, it is becoming clear that vesicle-mediated communication has a major influence on key aspects of cancer growth and progression. We conclude that the design of future therapeutics should acknowledge the existence and roles of extracellular vesicles, and seriously consider strategies for circumventing their effects in vivo. Copyright © 2015. Published by Elsevier Ltd.
    No preview · Article · Feb 2015 · Seminars in Cell and Developmental Biology
Show more